<template>
  <div class="cmt-container">
    <h3>发表评论</h3>
    <hr>
    <textarea v-model="msg" placeholder="请输入要BB的内容(最多120字)" maxlength="120"></textarea>
    <mt-button type="primary" size="large" @click="postComment">发表评论</mt-button>

    <div class="cmt=list">
      <div class="cmt-item" v-for="(item,index) in comments" :key="item.add_time">
        <div class="cmt-title">
          第{{index +1}}楼&nbsp;&nbsp;用户: {{item.user_name}}&nbsp;&nbsp;发表时间:{{item.add_time | dateFormat}}
        </div>
        <div class="cmt-body">
          {{item.content == 'undefined'? '此用户很懒,啥子都不说': item.content}}

        </div>
      </div>
    </div>

    <mt-button type="danger" size="large" plain @click='getMore'>加载更多</mt-button>
  </div>
</template>

<script>
  import { Toast } from 'mint-ui'
  export default {
    name: 'Comment',
    data() {
      return {
        // 默认展示第一页
        pageIndex: 1,
        //所有的评论数据
        comments: [],
        // 评论输入的内容
        msg: ''
      }
    },
    props: ["id"],
    created() {
      this.getComments()
    },
    methods: {
      getComments() {
        // 获取评论
        this.$http
          .get("api/getcomments/" + this.id + "?pageindex=" + this.pageIndex)
          .then(result => {
            if (result.body.status === 0) {
              // this.comments = result.body.message;
              // 每当获取新评论数据的时候，不要把老数据清空覆盖，而是应该以老数据，拼接上新数据
              this.comments = this.comments.concat(result.body.message);
            } else {
              Toast("获取评论失败！");
            }
          });
      },
      getMore() {
        this.pageIndex++;
        this.getComments()
      },
      postComment() {
        // 校验是否为空
        if (this.msg.trim().length == 0) {
          return Toast("评论内容不能为空")
        }

        // 参数1: 请求的url地址
        // 参数2: 提交给服务器的数据对象
        // 参数3: 定义提交时候表单的数据格式(emulateJSON)
        this.$http
          .post("api/postcomment/" + this.$route.params.id, {
            content: this.msg.trim()
          })
          .then(function(result) {
            if (result.body.status === 0) {
              // 1. 拼接出一个评论对象
              var cmt = {
                user_name: "匿名用户",
                add_time: Date.now(),
                content: this.msg.trim()
              };
              this.comments.unshift(cmt);
              this.msg = "";
            }
          });
      }
    },
  }
</script>

<style lang="scss" scoped>
  .cmt-container {
    h3 {
      font-size: 18px;
    }

    textarea {
      font-size: 14px;
      height: 85px;
      margin: 0;
    }

  }

  .cmt-list {
    margin: 5px 0;
  }

  .cmt-item {
    font-size: 13px
  }

  .cmt-title {
    line-height: 30px;
    background-color: #ccc;
  }

  .cmt-body {
    line-height: 35px;
    text-indent: 2em;
  }
</style>